Gen. John Hyten, Commander, U.S. Air Force Space Command, talks about the task of tracking all the materials in orbit and keeping them from crashing into each other. Steve Mirsky and Larry Greenemeier report

According to sports economist Andrew Zimbalist, most cities that win the right to host the Olympics will spend far more to prepare for the games than they estimate in their winning bid. Steve Mirsky reports

Scientific American health and medicine correspondent Dina Fine Maron talks with Armand Sprecher of Doctors Without Borders, who has fought Ebola in Guinea and Liberia. And Steve talks Ebola with Stanford's David Relman, chair of the Forum on Microbial Threats of the Institute of Medicine

Protected land and sea areas serve the wildlife within them as well as the humans who live near them. But countries are backtracking on their financial commitments to these vital regions. Steve Mirsky reports